The present invention relates to a disposable manometer for use with a source of respiratory gases such as a cardio-pulmonary resuscitator (CPR) bag or other ventilation devices. In the prior art, manometers are known, however, such devices do not include all of the features and aspects of the present invention. For example, U.S. Pat. No. 3,975,959 to Larkin which discloses a pressure gauge including a dial with an indicator pointer connected to a cylindrical follower having projections coupled with grooves formed in a stem portion connected to a movable wall. The movable wall is exposed to a source of air pressure and reciprocates the stem portion directly responsive to changes in air pressure to cause rotation of the follower and the pointer. Devices of the prior art will not provide accurate readings when exposed to the strong electromagnetic radiation of various clinical devices such as a Magnetic Resonance Imaging (MRI) system.
Another example is shown in U.S. Pat. No. 5,557,049 to Jeffrey B. Ratner which discloses a disposable manometer. The disclosed manometer has a typical metal spring that operates correctly in most situations but the use of such a manometer in the vicinity of an operational Magnetic Resonance Imaging (MRI) system often results in either a false pressure reading due to the extreme magnetic fields produced by the Magnetic Resonance Imaging system or, in extreme cases, such a manometer is often moved, possibly quickly, creating the possibility of inflicting injuries or damaging equipment.
Applicant is not aware of any helix-style manometer device that, prior to this invention, provides accurate readings in the presence of magnetic fields of devices such as a Magnetic Resonance Imaging (MRI) system.
What is needed is a helix style manometer device that will provide accurate readings in the presence of magnetic fields of a Magnetic Resonance Imaging (MRI) system.